Characteristics and Origins of the Solar System

Sample Examination: Updated Version

September 21,2000

 

Reminder: Bring your SC1 charts to the exam,  folks; you might be asked questions that will require them.  Answer these questions in complete sentences and always give your reasons, or state the principle/mathematical relation you are using.  Mere numbers and primal grunts written down are not adequate responses. Also be sure to bring a calculator to the exam: there will be numerical questions.

 

  1. Define the ecliptic.  You should describe what is corresponds to observationally (i.e. what we see in the sky that corresponds to the ecliptic) as well as the physical definition (i.e. what it is within the context of a model  of the solar of the solar system.
  2. Define what is meant by meridian and local mean noon.
  3. A friend tells you she saw Jupiter near the star Altair (Right Ascension 19h 51m, Declination +8˚ 51′  on the evening of September 1.  Is this a correct observation?  Give your reasons for accepting or rejecting it.
  4. Here’s a tough one; take your time to think about it and look over your SC1 chart! The line of nodes of the Moon’s orbit points to two places on the sky.  One is at Right Ascension = 20hours, Declination = -23 degrees, the other is at  Right Ascension 8 hours, Declination = +22 degrees.  The date is now January 13 and the Moon is at first quarter in the constellation of  Aries (around Right Ascension 2hours).  Will there be any eclipses in the near future?  What kind?
  5. Describe the basis of radioisotope dating of rocks.  The length of your response should be approximately one handwritten (single side page).  Continuing to a second page is OK, but don’t get carried away and write the libretto to a baroque opera.
  6. You are chosen as the Pontifex Maximus  (or Pontifatrix Maxima as the case may be) of the United States, a priestly office in which you get to decide things about time, definitions of the calendar, etc.  You decide these leap years are a bunch of confusing nonsense and decide that every year will consist of  365 days (mean solar days).  How long will it be until we are celebrating New Year’s Eve on the shortest night of the year?  Describe why this would happen.
  7. The orbits of planets around the Sun can be described by a certain mathematical figure.  What is this figure, and what is the scientific term for the law that says this is so?  Make a rough, Cro-Magnon-like cave drawing representation of this figure, and indicate some of  its important features.
  8. You have been abducted by space aliens!!!  They take you to the star 18 Scorpii, which is believed to be identical to the Sun, as far as we can tell.  They dump you on a planet there.  At its closest to the star (the fancy term for this is periastron) the planet is 0.5 astronomical units from 18 Scorpii.  At the most distant point in its orbit (apastron)  it is 1.5 astronomical units from the star.  (a) What is the length of the “year” for this planet? (b) Compare the rates at which the Sun moves against the background stars at periastron and apastron. 
  9. Define what is meant by astronomical unit and give its value (at least roughly).
  10. Of what elements is the Earth principally composed?  Compare its chemical composition with that of the Sun and stars.
  11. The sidereal day is about 4 minutes shorter than the mean solar day.  Explain why this difference exists.  In the case of  this problem, one well-done diagram is worth Avogadro’s Number of words. 
  12. Describe the characteristics of the rocks which comprise the continents and the ocean bottoms.  Use as many technical terms as you feel comfortable with. 
  13. The subject of geology comprises many interesting phenomena including formation of mountains, volcanism, Earthquakes, and others.  According to our modern understanding of geology, all of  these phenomena arise as a consequence of an important, general dynamism of the Earth.  What is this?  Discuss how the aforementioned phenomena (and others) arise as a consequence.  
  14. Radioisotope A undergoes Beta Decay to isotope B with a half life of 2 billion years. Analysis of a rock shows that it has 75 nuclei of  A per cubic centimeter and 25 of  B.  What can you say about the age of this rock?  Make the usual dubious assumption that the rock formed with no nuclei of  B.
  15. Comet Hale-Bopp (which appeared in the inner solar system in 1997) had an orbital period of about 5000 years.  How far from the Sun is it at aphelion?
  16. Discuss similarities and differences between the atmosphere of the Earth and those of the other terrestrial planets.
  17. How long ago did the Earth form? What evidence do we have for this? Roughly how long ago did animals appear (evolve) that you would want to have as a pet?